Cesarian scar endometriosis

Last revised by Mostafa Elfeky on 4 Feb 2024

Cesarian scar endometriosis can be located in the skin, subcutaneous tissue, rectus muscle/sheath, intraperitoneally, or in the uterine myometrium (within uterine scar).

The reported incidence of abdominal scar endometriosis following cesarean section is 0.03-0.6% 6.

Patients may complain of tenderness to palpation and a raised hypertrophic scar. Most patients have cyclical pain (up to 70%) 5. The pain is usually intermittent and associated with the patient's menstrual cycle but it may be constant. Some reports state that only as low as 20% of the patients exhibited cyclical symptoms. The overlying skin may be hyperpigmented due to the deposition of hemosiderin. Some patients may be asymptomatic 4.

It is thought to be caused by the implantation of endometrial stem cells at the surgical site at the time of uterine surgery.

To achieve a definitive diagnosis, histopathology is mandatory. It may detect endometrial-type glands, endometrial-type stroma, and/or hemosiderin-laden macrophages and must display two of the aforementioned three components 11.

For general imaging features of endometriosis: refer to the parent article.

Imaging studies should ideally be carried out during the menstrual cycle 10.

In general, lesions found along the visible abdominal wall scar and along the predicted path of a previous cesarian section scar should initially raise concern for this diagnosis in imaging studies 9.

Because of its larger field of view and reproducibility, MRI is better than ultrasound and can help identify more areas of endometriosis development 14. Furthermore, because of its greater tissue property characterization and lack of ionizing radiation, it is advantageous to CT 4.

Ultrasound may be of limited value if lesions have developed deeply within the abdominal cavity and are not superficially situated within the abdominal wall 8. Additionally, sonographic features are not specific. A subcutaneous nodule having relatively irregular borders, a heterogeneous, but predominantly hypoechoic echotexture with internal scattered hyperechoic echoes surrounded by a hyperechoic ring of variable width, and vascularity may be present. Occasionally cystic changes may be present 6.

Due to the nonspecific and frequently inconclusive sonography findings, ultrasound is primarily useful for image-guided tissue biopsy of suspected lesions and for confirming or ruling out other conditions included in the differential diagnosis 9. Those may include lipomas, suture granulomas, incisional or other types of abdominal wall hernias, etc 4. In most other situations, further imaging will be necessary.

On CT imaging, they may appear as a solid soft-tissue mass with spiculated margins and mild/moderate enhancement after IV contrast material 9,12. The lesions will usually be found close to and/or along the path of the previous cesarian section scar.

However, CT has limited use in the diagnosis of scar endometriosis given its limited contrast resolution and unnecessary radiation exposure 9. Therefore, in combination with the non-specific imaging manifestations it displays, it is not an imaging technique advised to be performed upon suspicion of this condition 13. Nevertheless, cesarian-section scar endometriosis may often clinically manifest as another disease (i.e., abdominal wall hernia, appendicitis, etc.) and thus be discovered incidentally with CT performed to exclude other diagnosis 9

The most sensitive imaging modality. Often accurately locates the lesion in relation to a previous C-section scar, with signal characteristics similar to that of background endometriosis.

  • T1: intermediate or mildly hyperintense lesion with hyperintense-hemorrhagic foci both on non-fat-saturated and fat-saturated images and a low signal rim (due to hemosiderin) 9

  • T2: mostly hypointense lesions that may display small hyperintense foci, a low signal rim (due to hemosiderin), and poorly defined infiltrative margins 9

  • T2: may further enhance the detection of hemosiderin given the increased sensitivity of this sequence to susceptibility artifacts 15

  • T1C+: usually demonstrates contrast enhancement; contrast-enhanced dynamic MRI may also be of assistance 16

  • DWI: lesions may demonstrate restricted diffusion 10

Surgical excision with clear resection margins is the favored treatment in symptomatic patients. Nevertheless, over the past few years, interventional radiology procedures using minimally invasive, percutaneous techniques (such as radiofrequency ablation, cryoablation, sclerotherapy, and high-intensity focused ultrasound) have also started to be implemented successfully, thus adding to the available treatment options 9.

Medical treatment with hormonal suppression (GnRH analogs) can offer temporary improvement in symptoms, with a low success rate 4

ADVERTISEMENT: Supporters see fewer/no ads